The calling party name feature is a Class 5 subscribed feature in the Public Switched Telephone network (PSTN). Incoming telephone calls to a subscriber's line may first query the appropriate Line Information Database (LIDB) for the calling party's name before terminating the telephone call. In the Session Initiation Protocol (SIP) domain, calling name information is typically provided, along with the calling number, for incoming telephone calls. This calling party name provisioning may be achieved by inserting the call originator's name in the Display-name field of the From or Remote-Party-Identifier (ID) header of the initial Invite message. For telephone calls originating in the PSTN and destined for the SIP domain, calling name information is typically not included.